Patent GB-1410071-A (GB)
Title: Method and apparatus for continuously producing flat folded corrugated containers
IPC: B31B5/00
Filed: 1972-08-16
Abstract: 1410071 Making flattened tubular containers; making corrugated board NISSO KK 16 Aug 1972 [17 Aug 1971] 38115/72 Headings B5D and B5N A method of continuously producing flat folded, corrugated containers includes forming one or two strips 4, Fig. 22, of double-faced corrugated board having longitudinally extending corrugations and stepped longitudinal edges 7a, 7b produced by laterally offsetting the liner strips 1, 2 from the corrugated strip 3 in opposite directions, continuously forming the corrugated board strip or strips 4 into a tubular body about a mandrel 17 so that the stepped edges are overlapped and adhered to one another, flattening the tubular body and severing the flattened body into container lengths. Prior to the formation of the tubular body, the or each strip is provided with longitudinal creases and may additionally be creased transversely and slit at spaced intervals along the longitudinal crease lines. Forming the double-face corrugated board strip. The liner strips 1, 2 are drawn from rolls 8, 9 and fed past adhesive applicator rollers 11a, 13a into the nip between rollers 12a, 12b. The strip 3 to be corrugated is drawn from a roll 10 and passes through a device 21 which sprays water on to the strip 3, through a corrugation forming device 23, between corrugation setting rollers 36, 37, past adhesive applicator rollers 14a, 14c and into the nip of rollers 12a, 12b. The corrugation forming device, Figs. 6 and 12, comprises rows of upper depending and lower upstanding plates 24, 25 carrying balls 29 at their lower and upper edges, respectively. The lateral spacing between adjacent upper plates 24 and the lateral spacing between adjacent lower plates 25 decreases in the direction of movement of the strip 3. Also the upper and lower plates 24, 25 gradually become intermeshed. The corrugation setting rollers 36, 37 can be steam heated and have mating ridges and grooves thereon which correspond in size to the corrugations formed. An automatic regulating device laterally displaces the liner strips 1, 2 relative to the corrugated strip in response to edge detectors located adjacent the edges of the three strips to maintain the stepped longitudinal edges when the three strips are brought together at the rollers 12a, 12b. Creasing and slitting.-The transverse creases are produced by a creasing roller (48, Fig. 16, not shown) mounted on a shaft (50) by springs (49) at both ends of the roller. The creasing roller (48) is driven through a reduction gear (54) through which the speed of rotation of the roller (48) can be adjusted to vary the spacing between the transverse creases formed in the strip 4 which moves past the roller (48) at a constant speed. The longitudinal creases are produced by creasing discs (57, Fig. 18, not shown) mounted on a shaft (58). The device for longitudinally slitting the strip 4 comprises rotatable discs 62, Fig. 20, carrying semicircular blades 63 which co-operate through slots in a plate 64 with slotting rollers 66. The discs 62 are driven through a reduction gear. Forming the tubular body.-The tubular body in its expanded condition may have a rectangular, hexagonal or octagonal cross-section. Adhesive is applied to the stepped longitudinal edges of the or each strip 4 to be formed into a tubular body by stepped adhesive applicator rollers 74, Fig. 21. If it is desired to make rectangular sectioned tubular bodies, the mandrel 17 comprises an upstream portion 17a of rectangular cross-section about which the strip or strips are formed and seamed, an intermediate portion 17b which has a changing rhomboidal crosssection to flatten the tubular body and an end portion 17c which is flat. The strip or strips 4 are formed about the mandrel by horizontally and vertically mounted rollers. The edge portions of the strip(s) 4 to be seamed may be arranged so that the corrugations overlap or abut one another at the seam. A steam heating coil (84, Fig. 23, not shown) is provided internally of the mandrel first portion 17a. The strip or strips 4 are continuously drawn along the mandrel 17 by a device 91 (Fig. 25, not shown) which includes endless feeding belts (98) co-operating with every side of the mandrel. The belts (98) which are magnetic, each pass around a driving roller (95) and an idling roller (96). The driving rollers (95) are driven from a single motor (103) though an arrangement of bevel gears (102, 109). Severing the tube lengths and stacking.-The tubular body is severed into lengths by a severing device 130 which comprises co-operating knives (133), Fig. 27 (not shown), operated by a solenoid (135). The so formed flat folded containers are stacked by a device 140.